Architecture and backend built to last in production

@RestController
class OrderHandler(private val service: OrderService) {

    @GetMapping("/orders/{id}")
    suspend fun get(@PathVariable id: String): ResponseEntity<OrderDto> =
        service.find(id)
            ?.let { ResponseEntity.ok(it.toDto()) }
            ?: ResponseEntity.notFound().build()

    @GetMapping("/orders/stream", produces = ["application/x-ndjson"])
    fun stream(): Flow<OrderDto> =
        service.updates()
            .map { it.toDto() }
            .buffer(64)
}

apiVersion: apps/v1
kind: Deployment
metadata:
  name: orders-api
spec:
  replicas: 3
  selector:
    matchLabels: { app: orders-api }
  template:
    metadata:
      labels: { app: orders-api }
    spec:
      containers:
        - name: app
          image: registry.example/orders-api:1.0.0
          readinessProbe:
            httpGet: { path: /actuator/health, port: 8080 }
          resources:
            limits: { cpu: "1", memory: 512Mi }